The present invention relates to a composite containing a stretched porous polytetrafluoroethylene layer which is highly compression resistant.
Stretched porous polytetrafluoroethylene has a low dielectric constant and has low dielectric loss and is not significantly frequency dependent. Therefore it is an outstanding dielectric material which is stable when used in high-frequency electrical applications. Nevertheless, it has the disadvantage of being poor in form stability and particularly being readily deformable under compression. Accordingly, it is an object of this invention to provide a composite article containing a layer of stretched porous polytetrafluoroethylene which is highly compression resistant.